SATRIX INVESTMENT ****MED ME!!

I invested with an agent called Grace Ndlovu and she promise me that I will receive my profit in two days. She said I must register on this website https://stxinvestment.com of whish I did. When it was time for withdrawal she said I must contact Arabella Mbally who will guide me on how to withdraw directly to my account. She guided me and said I will receive a notification email. Later in I receive an email saying I must pay R8000 for red withdrawal. How can that happen? I invested R2000 now I must pay R8000. This is a ****! I don't even have that kind of money